staging: wilc1000: use completion instead of struct semaphore hif_sema_wait_response

This patch replaces struct semaphore hif_sema_wait_response with struct
completion hif_wait_response. In case of struct hif_sema_wait_response,
it better to use completion than semaphore.

Signed-off-by: Chaehyun Lim <chaehyun.lim@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>